Ian ,
Newsflash straight from the Redding techline" our ackley dies size somewhat less than regular dies".George at GA Precision says that neck sizing dies normally size to within .040 of the neck. I'm sure that many on this site could have passed this info on but "we of less indentations on the gray matter" have been left to flounder on our own [img]/ubbthreads/images/graemlins/laugh.gif[/img]. So , since my measuring method of the unsized portion of the neck is less than stellar I would say that the Redding dies are leaving at least .020 unsized . I consider this a problem in the making and will request a new sleeve from Redding machined to size to within at least .040.Meanwhile,the lee collet dies do a very nice job of sizing the entire neck without disturbing the shoulder ( and quite probably insuring a smaller amount of runout thereby)
This saga will continue for as many months as I need to compare as honestly as my methods will permit.BTW, I suspect that the nomenclature used by Redding ( .243win imp 40* vs .243 AI) has as much to do with licensing problems as anything else , thus the confusion for folks not fully versed in these things,i.e. myself.
see ya! Jim

Jimm,
I got your email.
I didn't have time to read every post on this thread, but I am curious why you want to size the whole neck?
I only size about 2/3 to 1/2 the neck with my Redding comp dies on every caliber I own. The unsized portion of the neck helps "align" the cartridge in the chamber for ultimate stability and minimal sloppiness and brass movement upon firing.

Jimm,
I was about to sell my dies to an unsuspecting(not a member of this Forum) 243 Ackley shooter(only joking, that would be very unfair, but an absolute hoot, untill the poor guy gets put out of his misery!) but i shall take goodgroupers advice and see what happens.

I just want the ability to go in as many directions as possible to look for that "little bit of magic" that makes the difference.You know , the current trend is to forgo neck sizing alltogether ,"what's hot " is full length sizing with bushings for the neck! Well duhh,it seems that just as they are cycles in nature there are cyccles in the things men do to amuse themselves.I must admit that I am curious why the Redding dies in AI don't size as much as the rest of their dies(roughly .065 vs .040).However the Redding techline sent me a email today saying that they would make a sizing sleeve to my specs.They seem to be great folks to work with as they respond quickly and offer their expertise/opinion. preciate you response GG, (man,I'm loving this loopy mk with the tmr reticle).
Thanks , Jim

Hello Ian,
It's a shame you can't touch off some rounds at your hacienda [img]/ubbthreads/images/graemlins/frown.gif[/img].That's what I've been doing to fireform some loads while I wait on a scope back from Leupold( having target turrets installed on a vx3 4.5x14x40AO, cause the mk4 is for my .300winnie that Chris Matthews is finishing up as we speak)So, I could'nt wait to go shoot the .243Ai so I have been shooting and cleaning here for bbl. break in.(dang those fireformed cases are purty)
I loaded 38.0grs of IMR 4350 under 107 smk's seated to touch the rifling ,and no I did'nt chronograph the round ,heck, I was just shooting it in the dirt outside my reloading room to see the fireformed case then cleeeeaaaannnn!Also there were no pressure signs from the first. Anywho,I would'nt sell your dies just yet Ian,wait till you've put them to the test for your needs.There's nothing wrong with them ,I just want more control [img]/ubbthreads/images/graemlins/laugh.gif[/img]. Talk to you later, Jim